Study of Post-Yield Behavior of Trabecular Bone Using a 3-D Microstructural Model

In this study, a 3-D idealized microstructural finite element model was used to investigate post-yield behavior of trabecular bone. By assuming an elastic-plastic constitutive relation for trabecular tissue, we examined the failure process in an open-cell model. In addition, elastic buckling behavior of the model was quantified. The results of the plastic analysis indicate that localized collapse of trabeculae occurs at the peak of the stress-strain curve, resulting in a sharp increase in tissue strain in the collapsed regions. The buckling analysis shows that elastic buckling occurs at much higher strain levels (>20%). Therefore, it suggests that elastic buckling is unlikely a failure mechanism in trabecular bone with low density. These findings are consistent with previous 2-D finite element analysis and recent experimental observations.